Management of Small Urethrocutaneous Fistula by Tight Ligation with Fulguration of the External Epithelium of the Tract

Background/Purpose: Urethrocutaneous fistula (UCF) is the most common reported complication of hypospadias repair. The success of the operative technique is usually measured by its effectiveness in reduction of the incidence of UCF. Materials & Methods: In a prospective study, 11 patients with 12 small caliber fistulae were included. After identifying the fistulous opening, the fistula tract was circumferentially and meticulously dissected ,then the dissected tract was lifted up and the base was ligated tightly with 5/0 vicryl, the external epithelium of the dissected tract was fulgurated with the diathermy, then a second layer of local soft tissue was secured over the ligated fistula with 6/0 vicryl, followed by overlapping skin closure over the ligated stump with 5/0 vicryl rapid . Dressing with fucidin -tull and pressure dressing was applied to be removed after 24h with removal of the urethral catheter. Meatal stenosis and urethral stricture distal to the fistula was excluded in all the patients, except in one patient who was having meatal stenosis who had meatoplasty in the same time. Results: All fistulae healed nicely with no recurrence over 6 months follow up period. Conclusion: tight ligation of the UCF with fulguration of the epithelium of its tract is effective and successful in treating the small caliber UCF. It is non-time consuming, and not associated with any urethral stenosis or obstruction at the site of the ligated fistula.Index Word: Penile fistula, urethra-cutaneous fistula, ligation, hypospadias

Q factor limitation at short wavelength (around 300 nm) in III-nitride-on-silicon photonic crystal cavities

International audienceIII-nitride-on-silicon L3 and H2 photonic crystal cavities with resonances down to 315 nm and quality factors up to 1085 at 337 nm have been demonstrated. The reduction of quality factor (Q) with decreasing wavelength is investigated. Besides the QW absorption below 340 nm a noteworthy contribution is attributed to the residual absorption present in thin AlN layers grown on silicon, as measured by spectroscopic ellipsometry. This residual absorption ultimately limits the Q factor to around 250 at 300 nm when no active layer is present

Processing and characterization of alpha-elastin electrospun membranes

Elastin isolated from fresh bovine ligaments was dissolved in a mixture of 1,1,1,3,3,3-Hexafluoro-2-propanol and water were electrospun into fiber membranes under different processing conditions. Fiber mats of randomly and aligned fibers were obtained with fixed and rotating ground collectors and fibrils were composed by thin ribbons whose width depends on electrospinning conditions; fibrils with 721 nm up to 2.12 μm width were achieved. After cross-linking with glutaraldehyde, α-elastin can uptake as much as 1700 % of PBS solution and a slight increase on fiber thickness was observed. The glass transition temperature of electrospun fiber mats was found to occur at ˜80 °C. Moreover, α-Elastin showed to be a perfect elastomeric material, and no mechanical hysteresis was found in cycle mechanical measurements. The elastic modulus obtained for random and aligned fibers mats in a PBS solution was 330±10 kPa and 732±165 kPa, respectively. Finally, the electrospinning and cross-linking process does not inhibit MC-3T3-E1 cell adhesion. Cell culture results showed good cell adhesion and proliferation in the cross-linked elastin fiber mats.This work is funded by FEDER funds through the "Programa Operacional Factores de Competitividade-COMPETE" and by national funds arranged by FCT-Fundacao para a Ciencia e a Tecnologia, project references NANO/NMed-SD/0156/2007, PTDC/CTM-NAN/112574/2009, and PEST-C/FIS/UI607/2011. The authors also thank funding from "Matepro-Optimizing Materials and Processes", ref. "NORTE-07-0124-FEDER-000037", cofunded by the "Programa Operacional Regional do Norte" (ON.2-O Novo Norte), under the "Quadro de Referencia Estrategico Nacional" (QREN), through the "Fundo Europeu de Desenvolvimento Regional" (FEDER). The authors also thank support from the COST Action MP1003, 2010 'European Scientific Network for Artificial Muscles'. VS, JP, JS, and DMC thank the FCT for the SFRH/BD/48708/2008, SFRH/BD/64901/2009, SFRH/BPD/64958/2009 and SFRH/BPD/63148/2009, and SFRH/BD/82411/2011 grants, respectively. JLGR acknowledges the support of the Spanish Ministry of Science and Innovation through project No. MAT2010-21611-C03-01 (including the FEDER financial support). CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund